Numerous diagnosis tests are based upon the reaction in heterogeneous phase between a level and solid surface (typically a microscope slide) and a liquid phase.
In a first variation (such as for example serological tests), the biological sample to be tested is contained in the liquid phase, and reacts with a slide carrying reactive elements, for example proteins, cells, DNA sequences, bacteria, viruses, etc. placed in advance on the slide. After a first reaction, the slide is placed in contact with a revealing reagent.
According to another variation, the biological sample to be tested is placed on the slide, the reactive (antibodies, DNA or RNA probes, etc.) and revealing elements then being in the liquid phase. This is the case for example with histological tests where the sample is a tissue section taken from the organism of a patient.
Nowadays, these different operations for manipulating the solid phase and the liquid phase are essentially manual. Certain reagents are placed directly on the slide or, in the serological mode, it is the biological sample itself, then the slide or slides are soaked in successive baths which implement the dying operations necessary for the observation. Various disadvantages result from this, and in particular:                a risk of faulty manipulation when a sample of several microliters is placed on a slide and can slide outside of the reactive zone,        a lack of reproducibility because it is impossible to accurately control the shear stresses to which the deposit on the slide is subjected,        a drift of the reagents which, for reasons of cost, are not renewed with each soaking.        
The apparatuses currently available process the slides in the open with jets of liquid or baths, and this is associated with high consumption of reagent and a high risk of contamination. They are not adapted to random access use which alone is capable of responding to urgency. The apparatuses described for example in the patents or patent applications No. WO03/052386, U.S. Pat. No. 6,352,861 and U.S. Pat. No. 6,495,106 of LabVision, Ventana and BioGenex are of this type. They are adapted to immunohistology and are not used in serology.
There is therefore a real need for improved incubation devices for serology or histology slides which enable rapid, reliable and automated analysis. In the field of serology there is in particular an unsatisfied need for a random access slide incubator which can process a slide in short periods of time (typically in less than an hour) and respond to urgent diagnosis in the case of infectious diseases. This invention offers a solution to these needs.